JP7192902B2 - Antenna module and communication device - Google Patents

Description

The present invention relates to antenna modules and communication devices.

Conventionally, for example, in an antenna module used in a massive MIMO system, many patch antennas are used, so one patch antenna has one feeding point, and one patch antenna is configured to support only one polarized wave. Then it gets bigger. Therefore, a configuration in which one patch antenna has two feeding points has been disclosed (for example, Patent Document 1). As a result, one patch antenna can handle two polarized waves in different directions, and the size of the antenna module can be reduced.

Japanese Patent Publication No. 2000-508144

There is a problem that harmonics of the high-frequency signal used in the antenna module are output from the patch antenna, and an interfering wave received by the patch antenna is input to the LNA (low noise amplifier), causing the LNA to saturate. . On the other hand, it is conceivable to provide a filter for attenuating unwanted waves such as higher harmonics and interfering waves between the patch antenna and the high frequency circuit element (for example, RFIC). However, the filter is required for each of the two feeding points of one patch antenna. Therefore, depending on how the two filters are arranged in the antenna module, the size of the antenna module is increased.

SUMMARY OF THE INVENTION An object of the present invention is to reduce the size of an antenna module or the like including a patch antenna having two feeding points.

An antenna module according to an aspect of the present invention includes a multilayer substrate having a first principal surface and a second principal surface facing back to each other, and a radiation electrode and a ground electrode formed on the first principal surface side of the multilayer substrate. , a first filter, and a second filter different from the first filter, wherein the patch antenna includes a first feeding point and a second feeding point provided at different positions on the radiation electrode a point, the first feeding point electrically connected to the first filter, the second feeding point electrically connected to the second filter, the first filter and the second filter is formed in the multilayer substrate, and in a plan view of the multilayer substrate, the patch antenna and the first filter at least partially overlap each other, and the patch antenna and the second filter are at least Some are duplicated.

According to this, since the two filters, the first filter and the second filter, are not provided separately from the multilayer substrate but are formed within the multilayer substrate, the antenna module including the patch antenna having two feed points has the following advantages: It is possible to reduce the size while having filters corresponding to each of the two feeding points. In addition, since the first filter and the second filter electrically connected to the patch antenna formed on the first main surface side are formed in the multilayer substrate, there is no need to extend the wiring on the surface of the multilayer substrate, and the route wiring length can be shortened, and wiring loss can be suppressed. In addition, in a plan view of the multilayer substrate, the patch antenna and the first filter overlap at least partially, and the patch antenna and the second filter overlap at least partially. The visual size of the antenna module can be made smaller. In addition, since wiring can be provided directly below from the patch antenna to the first filter, and wiring can be provided directly below from the patch antenna to the second filter, wiring loss can be further suppressed.

Further, the direction of polarization formed by the first feeding point and the direction of polarization formed by the second feeding point may be different from each other.

According to this, one patch antenna can correspond to two polarized waves having directions different from each other, and since it is not necessary to provide a patch antenna for each polarized wave, the size of the antenna module can be reduced.

The passbands of the first filter and the second filter overlap at least partially, and high-frequency signals having the same frequency band are fed to the first feeding point and the second feeding point. good too.

According to this, the first filter and the second filter have substantially the same filter characteristics, and high-frequency signals having the same frequency band can pass through and can be transmitted and received with respect to each of the two feeding points. Unwanted waves can be similarly attenuated. Therefore, the antenna module can be applied to a MIMO system, which is a system that similarly processes signals passing through a plurality of signal paths.

Moreover, in a cross-sectional view of the multilayer substrate, the first filter and the second filter may be formed between the patch antenna and the second main surface.

Since the ground electrode functions as a ground conductor for the radiation electrode, it is preferable that no other conductor or the like be provided between the radiation electrode and the ground electrode. On the other hand, in the cross-sectional view, the radiation electrode and ground electrode, the first filter and the second filter, which constitute the patch antenna, are arranged in this order from the first main surface to the second main surface. That is, since the first filter and the second filter as other conductors or the like are not provided between the radiation electrode and the ground electrode that constitute the patch antenna, deterioration of the antenna characteristics can be suppressed.

Further, in a plan view of the multilayer substrate, the first filter is formed in one of two regions substantially symmetrical with respect to the center of the radiation electrode or a line passing through the center, and the first filter is formed in the other region. The second filter may be formed.

For example, since a multilayer substrate is provided with a filter for an IF (intermediate frequency) signal in addition to the first filter and the second filter, if two filters are provided for one patch antenna, the multilayer substrate The density of components (circuits) and wiring within the board makes it difficult to design a multi-layer board. On the other hand, by forming the first filter and the second filter in one and the other of the two substantially symmetrical regions, the components (circuits) and the wiring are arranged in the one region and the corresponding region in the multilayer substrate. It facilitates the design of multi-layer boards because it can be dispersed in other areas and not crowded.

A ground conductor may be formed between the first filter and the second filter.

According to this, the isolation characteristic between the first feeding point connected to the first filter and the second feeding point connected to the second filter can be improved.

Further, the first filter and the second filter may be electromagnetically coupled.

According to this, by allowing a signal opposite in phase to the unwanted signal leaking between the first feeding point and the second feeding point to flow in the coupling path between the first filter and the second filter, the unwanted signal is suppressed. can be offset.

Also, the first filter and the second filter may be LC filters.

This makes it easier to form the first filter and the second filter in the multilayer substrate. Also, the size of the first filter and the second filter can be reduced.

Moreover, the antenna module may include a plurality of sets of the patch antenna, the first filter, and the second filter, and the plurality of patch antennas may be arranged in a matrix on the multilayer substrate.

According to this, the antenna module can be applied to a Massive MIMO system.

Further, a communication device according to an aspect of the present invention includes the antenna module described above and a BBIC (baseband IC), and the antenna module up-converts a signal input from the BBIC to the patch antenna. An RFIC that performs at least one of transmission-system signal processing for outputting to the BBIC and reception-system signal processing for down-converting a high-frequency signal input from the patch antenna and outputting it to the BBIC.

According to this, it is possible to reduce the size of the communication device provided with the patch antenna having two feeding points.

According to the antenna module or the like according to the present invention, the size of the antenna module or the like provided with the patch antenna having two feeding points can be reduced.

FIG. 1 is an external perspective view of an antenna module according to Embodiment 1. FIG. 2 is a perspective side view of the antenna module according to Embodiment 1. FIG. 3 is a cross-sectional view showing another example of the first filter according to Embodiment 1. FIG. FIG. 4 is an external perspective view of an antenna module according to Embodiment 2. FIG. FIG. 5 is a perspective side view of the antenna module according to Embodiment 2. FIG. FIG. 6 is an external perspective view of an antenna module according to Embodiment 3. FIG. FIG. 7 is a perspective top view of an antenna module according to Embodiment 3. FIG. FIG. 8 is an external perspective view of an antenna module according to Embodiment 4. FIG. FIG. 9 is a configuration diagram showing an example of a communication device according to Embodiment 5. In FIG. FIG. 10 is an external perspective view of an antenna module according to another embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the embodiments described below are all comprehensive or specific examples. Numerical values, shapes, materials, components, arrangement of components, connection forms, and the like shown in the following embodiments are examples, and are not intended to limit the present invention. Among the constituent elements in the following embodiments, constituent elements not described in independent claims will be described as optional constituent elements. Also, the sizes or size ratios of components shown in the drawings are not necessarily exact. Moreover, in each figure, the same code|symbol is attached|subjected with respect to substantially the same structure, and the overlapping description may be abbreviate|omitted or simplified.

(Embodiment 1)
[1. Configuration of Antenna Module]
FIG. 1 is an external perspective view of an antenna module 1 according to an embodiment.

Hereinafter, the thickness direction of the antenna module 1 will be described as the Z-axis direction, the directions perpendicular to the Z-axis direction and perpendicular to each other will be described as the X-axis direction and the Y-axis direction, respectively, and the Z-axis positive side will be described as the upper surface side of the antenna module 1. do. However, in actual use, the thickness direction of the antenna module 1 may not be the vertical direction, so the upper surface side of the antenna module 1 is not limited to the vertical direction. The same applies to antenna modules according to Embodiments 2 to 4 and other embodiments, which will be described later.

The antenna module 1 shown in FIG. 1 can support two types of polarized waves both during transmission and reception, and is used for full-duplex communication, for example. In the present embodiment, the antenna module 1 corresponds to the two types of polarized waves, the polarized waves in the X-axis direction and the polarized waves in the Y-axis direction. That is, the antenna module 1 according to this embodiment supports two orthogonal polarized waves. Note that the antenna module 1 is not limited to this, and may be compatible with two polarized waves that form an angle different from orthogonal (for example, 75° or 60°).

The antenna module 1 includes a multilayer substrate 40 , a patch antenna 10 formed on the multilayer substrate 40 , a first filter 31 , a second filter 32 and a radio frequency circuit element (RFIC) 20 .

The multilayer substrate 40 has a first principal surface and a second principal surface facing each other. The first main surface is the main surface of the multilayer substrate 40 on the Z-axis plus side, and the second main surface is the main surface of the multilayer substrate 40 on the Z-axis minus side. The multilayer substrate 40 has a structure in which a dielectric material is filled between the first main surface and the second main surface. In FIG. 1, the dielectric material is made transparent to visualize the inside of the multilayer substrate 40, and the outline of the multilayer substrate 40 is indicated by broken lines. As the multilayer substrate 40, a low temperature co-fired ceramics (LTCC: Low Temperature Co-fired Ceramics) substrate, a printed substrate, or the like is used. As various conductors formed on the multilayer substrate 40, metals containing Al, Cu, Au, Ag, or alloys thereof as main components are used.

The patch antenna 10 is formed on the first main surface side of the multilayer substrate 40 and is composed of a radiation electrode 13 made of a thin film pattern conductor and a ground electrode 14 provided parallel to the main surface of the multilayer substrate 40 . For example, the radiation electrode 13 is provided on the first main surface, and the ground electrode 14 is formed on the second main surface side of the radiation electrode 13 . The radiation electrode 13 has, for example, a rectangular shape in plan view of the multilayer substrate 40, but may have a circular or polygonal shape. The ground electrode 14 is set to a ground potential and functions as a ground conductor for the radiation electrode 13 . Moreover, the radiation electrode 13 may be formed in the inner layer of the multilayer substrate 40 to prevent oxidation or the like, or a protective film may be formed on the radiation electrode 13 . Moreover, the radiation electrode 13 may be composed of a feeding conductor and a parasitic conductor arranged above the feeding conductor.

The RFIC 20 is formed on the second main surface side of the multilayer substrate 40 and configures an RF signal processing circuit that processes a transmission signal transmitted by the patch antenna 10 or a reception signal received by the patch antenna 10 . RFIC 20 has feed terminals 21 and 22 connected to patch antenna 10 . A ground conductor 24 is formed on the second main surface side of the multilayer substrate 40 , and for example, a ground terminal (not shown) of the RFIC 20 is connected to the ground conductor 24 . Although the RFIC 20 is provided on the second main surface of the multilayer substrate 40 in this embodiment, it may be built in the multilayer substrate 40 .

The patch antenna 10 has a first feeding point 11 and a second feeding point 12 through which high frequency signals are transmitted to and from the RFIC 20 . The first feeding point 11 and the second feeding point 12 are provided at different positions on the radiation electrode 13 . The direction of polarization formed by the first feeding point 11 and the direction of polarization formed by the second feeding point 12 are different from each other. A wave is formed and polarized in the X-axis direction by the second feeding point 12 . This makes it possible to support two polarized waves with one patch antenna. That is, since it is not necessary to provide a patch antenna for each polarized wave, the size of the antenna module can be reduced.

The first feeding point 11 is electrically connected to the RFIC 20 via the first filter 31 , and the second feeding point 12 is electrically connected to the RFIC 20 via the second filter 32 . Specifically, the first feeding point 11 is connected to the feeding terminal 21 of the RFIC 20 through the via conductor 41a, the first filter 31 and the via conductor 41b, and the second feeding point 12 is connected to the via conductor 42a, the second It is connected to the power supply terminal 22 of the RFIC 20 through the filter 32 and the via conductor 42b.

When the multilayer substrate 40 is viewed in the stacking direction (when the multilayer substrate 40 is viewed from above), the ground electrode 14 extends over substantially the entirety of the multilayer substrate 40 except, for example, portions where via conductors 41a and 42a are provided. are provided. Ground electrode 14 has an opening 14x through which via conductors 41a and 42a pass. Further, the ground conductor 24 is provided over substantially the entire multilayer substrate 40, except for the portions where the via conductors 41b and 42b are provided, for example, when the multilayer substrate 40 is viewed in the stacking direction. The ground conductor 24 has an opening 24x through which the via conductors 41b and 42b pass.

The first filter 31 and the second filter 32 are, for example, filters such as bandpass filters, highpass filters, or lowpass filters, and have a function of attenuating signals in specific frequency bands. The first filter 31 and the second filter 32 are different filters that are not integrally formed but separately formed. The passbands of the first filter 31 and the second filter 32 overlap at least partially. For example, the first filter and the second filter have substantially the same filter characteristics. Specifically, the passbands of the first filter 31 and the second filter 32 are substantially the same, and the attenuation bands of the first filter 31 and the second filter 32 are substantially the same. For example, since high-frequency signals having the same frequency band are fed to the first feeding point 11 and the second feeding point 12, the same filtering process is performed on the respective high-frequency signals.

A first filter 31 and a second filter 32 provided between the patch antenna 10 and the RFIC 20 pass high-frequency signals in the frequency band used by the patch antenna 10, and pass high-frequency signals (unwanted waves) in other frequency bands. has the function of attenuating Therefore, the harmonics can be attenuated so that the harmonics are not output from the patch antenna 10 as the unwanted waves. Moreover, the interfering wave received by the patch antenna 10 as the unwanted wave can be attenuated so that the interfering wave is not input to the LNA of the RFIC 20 and the LNA is saturated. In this way, unwanted waves that may be transmitted and received can be similarly attenuated for each of the two feeding points. Therefore, the antenna module 1 can be applied to a MIMO system, which is a system that similarly processes signals passing through a plurality of signal paths. The first filter 31 and the second filter 32 are realized by, for example, distributed constant lines, and more specifically by stubs, as shown in FIG.

[2. Arrangement of first filter and second filter in multilayer substrate]
The first filter 31 and the second filter 32 are formed within the multilayer substrate 40. The arrangement of the first filter 31 and the second filter 32 within the multilayer substrate 40 will be described with reference to FIG.

FIG. 2 is a perspective side view of the antenna module 1 according to Embodiment 1. FIG. In FIG. 2, the dielectric material is made transparent, the inside of the multilayer substrate 40 is visible, and the outline of the multilayer substrate 40 is indicated by broken lines. In FIG. 2, the via conductors 41a, 41b, 42a and 42b are hatched, but they do not represent cross sections.

As shown in FIGS. 1 and 2, in a plan view of the multilayer substrate 40, the patch antenna 10 and the first filter 31 at least partially overlap each other, and the patch antenna 10 and the second filter 32 at least partially overlap each other. Some are duplicated. Furthermore, the patch antenna 10, the first filter 31, and the RFIC 20 at least partially overlap, and the patch antenna 10, the second filter 32, and the RFIC 20 at least partially overlap. In the plan view, the via conductor 41a is formed in a region where the patch antenna 10 and the first filter 31 overlap, and the via conductor 41b is formed in a region where the first filter 31 and the RFIC 20 overlap. be. In the plan view, the via conductor 42a is formed in the region where the patch antenna 10 and the second filter 32 overlap, and the via conductor 42b is formed in the region where the second filter 32 and the RFIC 20 overlap. It is formed. Thus, since patch antenna 10 and first filter 31 and second filter 32 at least partially overlap each other, via conductors 41a and 42a are separated from patch antenna 10 by the first filter in the overlapping region. It can extend downward toward the filter 31 and the second filter 32 . In addition, since the RFIC 20 and the first filter 31 and the second filter 32 overlap at least partly, the via conductors 41b and 42b in the overlapping region are replaced by the first filter 31 and the second filter 31 and the via conductors 42b. It can extend straight down from the filter 32 towards the RFIC 20 .

Also, in a cross-sectional view of the multilayer substrate 40 , the first filter 31 and the second filter 32 are formed between the patch antenna 10 and the RFIC 20 . As described above, the patch antenna 10 includes the radiation electrode 13 and the ground electrode 14, and the dielectric material filled between the radiation electrode 13 and the ground electrode 14 is also called the patch antenna 10. That is, forming the first filter 31 and the second filter 32 between the patch antenna 10 and the RFIC 20 means that the first filter 31 and the second filter 32 are formed between the radiation electrode 13 and the ground electrode 14. means not

Although the first filter 31 and the second filter 32 are formed in the same layer in the multilayer substrate 40 as shown in FIG. 2, they may be formed in different layers in the multilayer substrate 40. FIG. When the first filter 31 and the second filter 32 are formed in different layers in the multilayer substrate 40, the first filter 31 and the second filter 32 are arranged so that at least a portion of the first filter 31 and the second filter 32 overlap in a plan view of the multilayer substrate 40. may be formed in That is, in the plan view, the patch antenna 10, the first filter 31, the second filter 32, and the RFIC 20 may at least partially overlap.

[3. Implementation example of the first filter and the second filter]
Although the first filter 31 and the second filter 32 are realized by distributed constant lines as shown in FIGS. 1 and 2, they may be LC filters. The first filter 31, which is an LC filter, will be described below with reference to FIG.

FIG. 3 is a cross-sectional view showing another example of the first filter 31 according to Embodiment 1. FIG. FIG. 3 schematically shows a cross section of a portion of the multilayer substrate 40 where the first filter 31 is formed. In addition, in FIG. 3 , for the sake of simplicity, there are cases where, strictly speaking, constituent elements in different cross sections are shown in the same drawing for explanation.

As shown in FIG. 3, the first filter 31 may be realized by an inductor L and a capacitor C formed within the multilayer substrate 40. As shown in FIG. The inductor L is configured by connecting ends of coil-shaped pattern conductors formed in each layer of the multilayer substrate 40 by via conductors. Via conductors connecting the coiled pattern conductors of each layer are formed in different cross sections. Also, the capacitor C is composed of a pair of pattern conductors facing each other. In FIG. 3, as an example of the first filter 31, the inductor L is connected between the via conductor 41a and the via conductor 41b, and the node between the via conductor 41a and the inductor L and the ground (ground electrode 14) are connected. A low-pass filter is shown with a capacitor C connected to . Since the second filter 32 can also be configured in the same manner as the first filter 31, the description thereof will be omitted.

[4. effect]
As described above, since the two filters of the first filter 31 and the second filter 32 are not provided separately from the multilayer substrate 40 but are formed within the multilayer substrate 40, the patch antenna having two feeding points Although the antenna module 1 having 10 has the first filter 31 and the second filter 32 corresponding to the first feeding point 11 and the second feeding point 12, respectively, the size is reduced. Also, a first filter 31 and a second filter 32 provided on a path connecting the RFIC 20 formed on the second main surface side and the patch antenna 10 formed on the first main surface side are formed in the multilayer substrate 40. Therefore, it is not necessary to extend the wiring on the surface of the multilayer substrate 40, the wiring length of the route can be shortened, and the wiring loss can be suppressed.

Moreover, in a plan view of the multilayer substrate 40, the patch antenna 10 and the first filter 31 at least partially overlap each other, and the patch antenna 10 and the second filter 32 at least partially overlap each other. , the size of the antenna module 1 in plan view can be further reduced. Specifically, the size in the X-axis direction and the Y-axis direction can be reduced. In addition, the wiring (via conductor 41a) can be provided directly below from the patch antenna 10 to the first filter 31, and the wiring (via conductor 42a) can be provided directly below from the patch antenna 10 to the second filter 32. , the wiring loss can be further suppressed.

In addition, since at least part of the RFIC 20 also overlaps with the patch antenna 10, the first filter 31 and the second filter 32 in a plan view of the multilayer substrate 40, the size of the antenna module 1 in the plan view can be reduced. Can be made smaller. Moreover, wiring (via conductors 41a and 41b) can be provided directly below from the patch antenna 10 to the first filter 31 and from the first filter 31 to the RFIC 20, and from the patch antenna 10 to the second filter 32, the second filter 32 can be provided. Since the wiring (via conductors 42a and 42b) can be provided directly below from to the RFIC 20, wiring loss can be further suppressed.

Further, when another conductor or the like is provided between the radiation electrode 13 and the ground electrode 14 constituting the patch antenna 10, the antenna characteristics may deteriorate. Since the first filter 31 and the second filter 32 are not provided, deterioration of antenna characteristics can be suppressed.

(Embodiment 2)
The antenna module 2 according to Embodiment 2 differs from the antenna module 1 according to Embodiment 1 in that ground via conductors 43 are formed in the multilayer substrate 40 . Since other points are the same as those of the antenna module 1 in the first embodiment, description thereof is omitted.

FIG. 4 is an external perspective view of the antenna module 2 according to the second embodiment. FIG. 5 is a perspective side view of the antenna module 2 according to the second embodiment. In FIGS. 4 and 5, the dielectric material is made transparent, the inside of the multilayer substrate 40 is visible, and the outline of the multilayer substrate 40 is indicated by broken lines. Although the via conductors 41a, 41b, 42a and 42b and the ground via conductor 43 are hatched in FIG. 5, they do not represent cross sections.

As shown in FIGS. 4 and 5, ground via conductors 43 are formed to connect ground electrodes 14 and ground conductors 24 . Ground via conductor 43 surrounds first filter 31 and second filter 32 and is formed along first filter 31 and second filter 32 . Thus, since the first filter 31 and the second filter 32 are surrounded by the ground conductor 24, the ground electrode 14 and the ground via conductor 43, high frequency signals can be propagated with low loss.

(Embodiment 3)
The antenna module 3 according to Embodiment 3 differs from the antenna module 2 according to Embodiment 2 in that ground via conductors 44 are formed as ground conductors in the multilayer substrate 40 . Since other points are the same as those of the antenna module 2 in Embodiment 2, description thereof is omitted.

FIG. 6 is an external perspective view of the antenna module 3 according to the third embodiment. FIG. 7 is a perspective top view of the antenna module 3 according to the third embodiment. In FIGS. 6 and 7, the dielectric material is made transparent, the inside of the multilayer substrate 40 is visible, and the outline of the multilayer substrate 40 is indicated by broken lines.

As shown in FIGS. 6 and 7, ground via conductors 44 are formed between first filter 31 and second filter 32 . Specifically, ground via conductor 44 is formed between first filter 31 and second filter 32 in plan view of multilayer substrate 40 . For example, the ground via conductors 44 are the four ground via conductors enclosed by the dashed-dotted lines shown in FIG. Since the first filter 31 and the second filter 32 are connected to the first feeding point 11 and the second feeding point 12 in one patch antenna, they can be formed close to each other. That is, unnecessary electromagnetic field coupling occurs between the first filter 31 and the second filter 32, and the first feeding point 11 connected to the first filter 31 and the second feeding point 11 connected to the second filter 32 The isolation characteristics between points 12 may be degraded. On the other hand, by forming the ground via conductor 44 between the first filter 31 and the second filter 32, the ground via conductor 44 acts as a barrier to suppress the occurrence of the unnecessary electromagnetic field coupling. Thereby, the isolation characteristics between the first feeding point 11 and the second feeding point 12 can be improved.

The ground conductor formed between the first filter 31 and the second filter 32 is not limited to the via-shaped ground via conductor 44, and may be a wall-shaped ground conductor. When the first filter 31 and the second filter 32 at least partially overlap each other in a plan view of the multilayer substrate 40, the first filter 31 and the second filter 32 overlap in a cross-sectional view of the multilayer substrate 40. A ground conductor parallel to the main surface of the multilayer substrate 40 may be formed therebetween.

(Embodiment 4)
Antenna module 4 according to Embodiment 4 includes a plurality of sets of patch antenna 10, first filter 31 and second filter 32 described in Embodiments 1 to 3, and the plurality of patch antennas are arranged in a matrix on a multilayer substrate. The arrangement is different from that of the antenna module 1 according to the first embodiment.

FIG. 8 is an external perspective view of the antenna module 4 according to the fourth embodiment. In FIG. 8, the dielectric material is made transparent so that the inside of the multilayer substrate 400 is visible, and the outline of the multilayer substrate 400 is indicated by dashed lines. The patch antennas 101 to 104, the first filters 311, 313, 315 and 317, the second filters 312, 314, 316 and 318, the multilayer substrate 400, and the RFIC 200 in Embodiment 4 are similar to the patches in Embodiments 1 to 3. It corresponds to the antenna 10 , the first filter 31 , the second filter 32 , the multilayer substrate 40 and the RFIC 20 . Note that FIG. 8 shows a portion of the multilayer substrate 400, and the antenna module 4 actually has many patch antennas in addition to the four patch antennas 101 to 104, making it applicable to a Massive MIMO system. ing.

In the multilayer substrate 400, the patch antenna 101 is composed of the radiation electrode 131 and the ground electrode 140, the patch antenna 102 is composed of the radiation electrode 132 and the ground electrode 140, and the patch antenna 103 is composed of the radiation electrode 133 and the ground electrode 140. The radiation electrode 134 and the ground electrode 140 constitute the patch antenna 104 . Although one ground electrode 140 is formed on the multilayer substrate 400, ground electrodes may be formed individually corresponding to the radiation electrodes.

A plurality of patch antennas 101 to 104 are periodically arranged in a matrix to form an array antenna. The array antenna is composed of four patch antennas 101 to 104 of 2 rows and 2 columns that are two-dimensionally orthogonally arranged (that is, arranged in a matrix) along the X-axis direction and the Y-axis direction. Note that the number of patch antennas forming the array antenna may be two or more. Also, the arrangement of the plurality of patch antennas is not limited to the above. For example, the array antenna may be composed of patch antennas arranged one-dimensionally or may be composed of patch antennas arranged in a zigzag pattern.

Further, as shown in FIG. 8, in a plan view of the multilayer substrate 400, one of two regions 401, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, 403, First filters 311 , 313 , 315 and 317 are formed in 405 and 407 and second filters 312 , 314 , 316 and 318 are formed in the other regions 402 , 404 , 406 and 408 . In FIG. 8, the dashed-dotted lines indicating the regions 401 to 408 are imaginary lines, and such lines are not actually provided in the multilayer substrate 400 . The shape of the two regions may be, for example, substantially triangular like regions 401 and 402, substantially rectangular like regions 403 and 404, regions 405 and 406, and region Opposing sides such as 407 and 408 may be stepped. In addition, the shape of the two substantially symmetrical regions is not limited to these, and may be other shapes. In addition, symmetry may be point symmetry with the center of the radiation electrode 131 as the central point as in the areas 401 and 402, or a line passing through the center of the radiation electrode 132 as in the areas 403 and 404. It may be symmetrical with respect to a line.

Multilayer substrate 400 is provided with a filter for an IF (intermediate frequency) signal, etc., in addition to the first filter and the second filter. Therefore, if two filters are provided for one patch antenna, the components (circuits) and wiring will be densely packed in the multilayer substrate 400, making the design of the multilayer substrate 400 difficult. On the other hand, by forming the first filter and the second filter in one and the other of the two substantially symmetrical regions, the components (circuits) and wiring in the multilayer substrate 400 are arranged in one region and the other. The design of the multilayer substrate 400 is facilitated because it can be dispersed in the other region and not crowded.

Further, the positions of the first feeding point and the second feeding point on each radiation electrode are not limited to the positions shown in FIG. In FIG. 8, the symbols of the first feeding point and the second feeding point are omitted. The feeding point to be used is the second feeding point. For example, in Embodiments 1 to 3, the position of the first feeding point 11 was located on the Y-axis minus side of the second feeding point 12. The positions of the first and second feeding points on the radiation electrode 131 and the positions of the first and second feeding points on the radiation electrode 132 are located on the Y-axis plus side of the second feeding point on the radiation electrode 132. It may be line symmetrical. Similarly, the position of the first feeding point on the radiation electrode 134 is positioned on the Y-axis plus side of the second feeding point on the radiation electrode 134, the positions of the first feeding point and the second feeding point on the radiation electrode 133, The positions of the first feeding point and the second feeding point on the radiation electrode 134 may be line symmetrical. Furthermore, in Embodiments 1 to 3, the position of the second feeding point 12 was located on the X-axis minus side of the first feeding point 11, but for example, the position of the second feeding point on the radiation electrode 133 is The position of the first feeding point and the second feeding point on the radiation electrode 131 and the position of the first feeding point and the second feeding point on the radiation electrode 133 are located on the X-axis plus side of the first feeding point on the radiation electrode 133. may be symmetrical with each other. Similarly, the position of the second feeding point on the radiation electrode 134 is located on the X-axis plus side of the first feeding point on the radiation electrode 134, and the position of the first feeding point and the second feeding point on the radiation electrode 132 The position and the positions of the first feeding point and the second feeding point on the radiation electrode 134 may be line symmetrical.

In this way, by making the positional relationship between the feeding points of adjacent patch antennas axisymmetric, it is possible to suppress degradation of XPD (Cross Polarization Discrimination) due to unnecessary polarized waves in the thickness direction of the multilayer substrate 400. .

(Embodiment 5)
The antenna module described above can be applied to communication devices. A communication device 60 to which the antenna module 4 according to the fourth embodiment is applied will be described below.

FIG. 9 is a configuration diagram showing an example of a communication device 60 according to Embodiment 5. As shown in FIG. For simplicity, FIG. 9 shows only the configuration corresponding to four patch antennas 101 to 104 out of the plurality of patch antennas provided in the antenna module 4, and the configuration corresponding to other patch antennas configured in the same manner. are omitted. Also, FIG. 9 shows a 4-antenna/2-stream configuration in which two streams correspond to four patch antennas.

The communication device 60 includes an antenna module 4 and a BBIC (baseband IC) 50 forming a baseband signal processing circuit. The RFIC 200 included in the antenna module 4 performs transmission system signal processing that up-converts the signal input from the BBIC 50 and outputs it to the patch antenna, and down-converts the high-frequency signal that is input from the patch antenna and outputs it to the BBIC 50 for reception. signal processing of the system. In this embodiment, the RFIC 200 performs both transmission system signal processing and reception system signal processing.

The RFIC 200 includes switches 21A to 21H, 23A to 23H, 27A and 27B, power amplifiers 22AT to 22HT, low noise amplifiers 22AR to 22HR, attenuators 24A to 24H, phase shifters 25A to 25H, and signal synthesis/dividing. It comprises wavers 26A and 26B, mixers 28A and 28B, and amplifier circuits 29A and 29B.

For each stream, the signal transmitted from BBIC 50 is amplified by amplifier circuits 29A and 29B and upconverted by mixers 28A and 28B. A transmission signal, which is an up-converted high-frequency signal, is divided into eight by signal combiners/dividers 26A and 26B, passes through eight signal paths, and is fed to patch antennas 101-104. At this time, the directivity of the array antenna composed of patch antennas 101-104 can be adjusted by individually adjusting the degree of phase shift of phase shifters 25A-25H arranged in each signal path.

Also, the received signals, which are high-frequency signals received by the patch antennas 101 to 104, respectively, pass through eight different signal paths, are multiplexed by the signal combiner/demultiplexers 26A and 26B, and are downloaded by the mixers 28A and 28B. It is converted, amplified by amplifier circuits 29A and 29B, and transmitted to BBIC50.

The RFIC 200 is formed, for example, as a one-chip integrated circuit component including the circuit configuration described above.

The switches 21A to 21H, 23A to 23H, 27A and 27B switch the signal path on the transmission side and the signal path on the reception side in accordance with control signals input from a control section such as the BBIC 50. FIG. The communication device 60 shown in FIG. 9 configured in this way supports the TDD system in which the transmission signal and the reception signal are transmitted or received at different timings.

In addition, the communication system with which the antenna module 4 and the communication apparatus 60 respond|correspond is not restricted to this. For example, the antenna module 4 and the communication device 60 may be compatible with a system in which transmission and reception are performed at the same time, such as the PDD system or the FDD system. That is, multiple patch antennas may simultaneously transmit and receive transmit and receive signals. In particular, since the antenna module 4 can support two types of polarized waves both during transmission and during reception, it is useful as an antenna module with high communication quality used for dual polarized full-duplex communication. be.

The switches 21A to 21H, 23A to 23H, 27A and 27B, the power amplifiers 22AT to 22HT, the low noise amplifiers 22AR to 22HR, the attenuators 24A to 24H, the phase shifters 25A to 25H, and the signal combiner/demultiplexer 26A are described above. and 26B, mixers 28A and 28B, and amplifier circuits 29A and 29B may not be included in RFIC 200. FIG. Also, the RFIC 200 may have only one of the transmission path and the reception path. Moreover, the communication device 60 can be applied not only to a system that transmits and receives high-frequency signals of a single frequency band (band), but also to a system that transmits and receives high-frequency signals of a plurality of frequency bands (multi-band).

By applying any one of the antenna modules 1 to 4 to the communication device 60 having the above configuration, miniaturization is achieved.

(Other embodiments)
As described above, the antenna module according to the embodiment of the present invention has been described with reference to the above embodiment, but the present invention is not limited to the above embodiment. Another embodiment realized by combining arbitrary constituent elements in the above embodiment, and a modification obtained by applying various modifications that a person skilled in the art can think of without departing from the scope of the present invention to the above embodiment Examples are also included in the invention.

For example, in the above embodiment, the patch antenna 10 has one feed point to form one polarized wave, but the present invention is not limited to this. For example, patch antenna 10 may have two feed points to form one polarization. This will be described with reference to FIG. 10 .

FIG. 10 is an external perspective view of an antenna module 1a according to another embodiment.

In the antenna module 1a according to another embodiment, the patch antenna 10 has two feeding points for forming polarized waves in the X-axis direction, and two feeding points for forming polarized waves in the Y-axis direction. The antenna module 1 differs from the antenna module 1 according to the first embodiment in that it has two feeding points. Since other points are the same as those of the antenna module 1 in the first embodiment, description thereof is omitted.

The patch antenna 10 has a first feeding point 11, a second feeding point 12, a third feeding point 11a, and a fourth feeding point 12a through which high-frequency signals are transmitted to and from the RFIC 20. FIG. These feeding points are provided at different positions on the radiation electrode 13 . The first feeding point 11 and the third feeding point 11a are connected to each other to form polarized waves in the Y-axis direction, and the second feeding point 12 and the fourth feeding point 12a are connected to each other. A polarized wave in the X-axis direction is formed. In FIG. 10, the connection between the first feeding point 11 and the third feeding point 11a and the connection between the second feeding point 12 and the fourth feeding point 12a are omitted.

For example, a first pattern conductor is provided in the inner layer of the multilayer substrate 40 to connect the first feeding point 11 and the third feeding point 11a. For example, by connecting the via conductor 41a connected to the first feeding point 11 and the via conductor 43a connected to the third feeding point 11a by the first pattern conductor, the first feeding point 11 and the third feeding point 11a are connected. are connected. The first pattern conductor is a path extending from a path extending from the first filter 31 to the via conductor 41a and extending to the via conductor 43a. The first pattern conductor is provided, for example, in a layer of the multilayer substrate 40 different from that of the second pattern conductor, which will be described later. By adjusting the pattern length of the first pattern conductor, the third feeding point 11a is fed with a phase difference of 180 degrees from the first feeding point 11a.

Further, for example, a second pattern conductor is provided in the inner layer of the multilayer substrate 40 to connect the second feeding point 12 and the fourth feeding point 12a. For example, the via conductor 42a connected to the second feeding point 12 and the via conductor 44a connected to the fourth feeding point 12a are connected by the second pattern conductor so that the second feeding point 12 and the fourth feeding point 12a are connected. are connected. The second pattern conductor is a path that branches from the path from the second filter 32 to the via conductor 42a and reaches the via conductor 44a. By adjusting the pattern length of the second pattern conductor, the fourth feeding point 12a is fed with a phase difference of 180 degrees from the second feeding point 12a.

In this way, the first feeding point 11 and the third feeding point 11a fed with a phase difference of 180 degrees form polarized waves in the Y-axis direction, and the second feed point 11a fed with a phase difference of 180 degrees forms a polarized wave in the Y-axis direction. A polarized wave in the X-axis direction is formed by the feeding point 12 and the fourth feeding point 12a. In other words, since the power is supplied with a phase difference of 180 degrees for each polarized wave, degradation of XPD due to unnecessary polarized waves in the thickness direction of the multilayer substrate 40 can be suppressed.

The third feeding point 11a is connected to the first feeding point 11 connected to the first filter 31, and the fourth feeding point 12a is connected to the second feeding point 12 connected to the second filter 32. . That is, it is not necessary to newly provide a filter for the third feeding point 11a and the fourth feeding point 12a, and it is sufficient to provide one filter for each polarized wave. Even if it is formed, it is possible to reduce the size of the antenna module 1a.

In the antenna modules 2 to 4 as well, the patch antenna may have two feeding points for each polarized wave like the antenna module 1a.

Further, for example, by forming a ground conductor between the first filter 31 and the second filter 32, the isolation characteristics between the first feeding point 11 and the second feeding point 12 are improved. However, by forming the first filter 31 and the second filter 32 so as to be closer to each other in some parts, electromagnetic field coupling may be positively effected. For example, by not forming part of the plurality of ground via conductors 44 shown in FIGS. A first filter 31 and a second filter 32 are formed to be close to each other. At this time, the first filter 31 and the The second filter 32 is electromagnetically coupled. Thereby, the unnecessary signal can be canceled.

Further, for example, in a cross-sectional view of the multilayer substrate 40, the first filter 31 and the second filter 32 are formed between the patch antenna 10 and the RFIC 20, but the radiation electrode 13 and the ground electrode 14 constituting the patch antenna 10 may be formed between

Further, for example, in a plan view of the multilayer substrate 40, the patch antenna 10, the first filter 31, and the RFIC 20 at least partially overlap each other, and the patch antenna 10, the second filter 32, and the RFIC 20 at least partially overlap each other. was duplicated, but it does not have to be duplicated.

Also, for example, the antenna modules according to the above embodiments can be applied to Massive MIMO systems. One of the promising radio transmission technologies for 5G (5th generation mobile communication system) is a combination of phantom cells and Massive MIMO systems. A phantom cell is a network configuration that separates control signals to ensure communication stability between low-frequency-band macrocells and high-frequency-band small cells from data signals for high-speed data communication. . Each phantom cell is provided with a Massive MIMO antenna device. A Massive MIMO system is a technique for improving transmission quality in the millimeter wave band or the like, and controls the directivity of the antenna by controlling the signal transmitted from each patch antenna. Also, since the Massive MIMO system uses a large number of patch antennas, it can generate sharp directional beams. By improving the directivity of the beam, it is possible to send radio waves over a certain distance even in a high frequency band, and at the same time, it is possible to reduce interference between cells and improve frequency utilization efficiency.

INDUSTRIAL APPLICABILITY The present invention can be widely used in communication equipment such as Massive MIMO systems as an antenna module that can be miniaturized.

1, 1a, 2, 3, 4 antenna module 10, 101 to 104 patch antenna 11 first feeding point 12 second feeding point 11a third feeding point 12a fourth feeding point 13, 131 to 134 radiation electrode 14, 140 ground electrode 14x, 24x aperture 20, 200 high frequency circuit element (RFIC)
21A to 21H, 23A to 23H, 27A, 27B Switch 22AR to 22HR Low noise amplifier 22AT to 22HT Power amplifier 24A to 24H Attenuator 25A to 25H Phase shifter 26A, 26B Signal synthesis/demultiplexer 28A, 28B Mixer 29A, 29B Amplification Circuits 21, 22, 211 to 218 Feeding terminals 24, 240 Ground conductors 31, 311, 313, 315, 317 First filters 32, 312, 314, 316, 318 Second filters 40, 400 Multilayer substrates 41a, 41b, 42a, 42b, 43a, 44a via conductors 43, 44 ground via conductors 50 baseband IC (BBIC)
60 communication device 401 to 408 area C capacitor L inductor

Claims (11)

a multilayer substrate having a first main surface and a second main surface facing away from each other;
a patch antenna formed on the first main surface side of the multilayer substrate and configured from a radiation electrode and a ground electrode;
a first filter;
a second filter different from the first filter,
The patch antenna has a first feeding point and a second feeding point provided at different positions on the radiation electrode,
The first feeding point is electrically connected to the first filter,
the second feeding point is electrically connected to the second filter;
the first filter and the second filter are formed in the multilayer substrate;
In a plan view of the multilayer substrate, the patch antenna and the first filter at least partially overlap, and the patch antenna and the second filter at least partially overlap ,
The first filter is formed to extend from the first feeding point,
The second filter is formed to extend from the second feeding point,
The direction in which the first filter extends and the direction in which the second filter extends are different from each other,
antenna module. The direction of polarization formed by the first feeding point and the direction of polarization formed by the second feeding point are different from each other,
Antenna module according to claim 1. The passbands of the first filter and the second filter are at least partially overlapping,
high-frequency signals having the same frequency band are fed to the first feeding point and the second feeding point, respectively;
The antenna module according to claim 1 or 2. In a cross-sectional view of the multilayer substrate, the first filter and the second filter are formed between the patch antenna and the second main surface,
The antenna module according to any one of claims 1-3. In a plan view of the multilayer substrate, the first filter is formed in one of two regions substantially symmetrical with respect to the center of the radiation electrode or a line passing through the center, and the first filter is formed in the other region. 2 filters are formed,
The antenna module according to any one of claims 1-4. A ground conductor is formed between the first filter and the second filter;
The antenna module according to any one of claims 1-5. wherein the first filter and the second filter are LC filters;
The antenna module according to any one of claims 1-6. The antenna module comprises a plurality of sets of the patch antenna, the first filter and the second filter,
The plurality of patch antennas are arranged in a matrix on the multilayer substrate,
The antenna module according to any one of claims 1-7. In the multilayer substrate, the first filter and the second filter are formed in the same layer,
Antenna module according to claim 1. An antenna module,
a multilayer substrate having a first main surface and a second main surface facing away from each other;
a patch antenna formed on the first main surface side of the multilayer substrate and composed of a radiation electrode and a ground electrode;
a first filter;
a second filter different from the first filter,
The patch antenna has a first feeding point and a second feeding point provided at different positions on the radiation electrode,
The first feeding point is electrically connected to the first filter,
the second feeding point is electrically connected to the second filter;
the first filter and the second filter are formed in the multilayer substrate;
The antenna module includes a first electrode group and a second electrode group provided at different positions when the multilayer substrate is viewed from above,
The first electrode group has the radiation electrode, the first filter and the second filter,
The second electrode group has the radiation electrode, the first filter and the second filter that are different from the radiation electrode, the first filter and the second filter of the first electrode group,
The first filter of the first electrode group has a part that faces the radiation electrode of the first electrode group and another part that does not face the radiation electrode of the second electrode group, and faces the radiation electrode of the second electrode group. without
The second filter of the first electrode group has a part that faces the radiation electrode of the first electrode group and another part that does not face the radiation electrode of the second electrode group, and faces the radiation electrode of the second electrode group. do not,
antenna module. An antenna module according to any one of claims 1 to 10 ;
BBIC (baseband IC),
The antenna module performs transmission system signal processing for up-converting a signal input from the BBIC and outputting it to the patch antenna, and down-converting a high-frequency signal input from the patch antenna and outputting it to the BBIC. An RFIC that performs at least one of reception system signal processing,
Communication device.

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